In conventional manner, the dispenser head comprises a fluid dispenser member, such as a pump or a valve. The dispenser member generally comprises a body that is mounted in stationary manner relative to the reservoir, and a valve rod that is axially displaceable down and up relative to the body. The dispenser head also comprises a pushbutton that is axially displaceable down and up, driving the valve rod. In order to expel the fluid, the dispenser head also includes a dispenser orifice that is connected to the valve rod. Thus, by pressing on the pushbutton by means of one or more fingers, the valve rod is pushed into the body of the dispenser member, thereby dispensing the fluid from the reservoir, optionally in metered manner.
In such a conventional dispenser head, the only possible displacement of the pushbutton is axial displacement down and up, imparted by the user who presses by means of one or more fingers on a thrust surface formed by the pushbutton. Since the pushbutton is coupled directly to the valve rod, its displacement drives the displacement of the valve rod directly. In other words, the pushbutton and the valve rod are displaced together, simultaneously.
In the prior art, dispenser heads are also known provided with pushbuttons that are displaceable in turning about their displacement axis in order to achieve a locking function for the pushbutton. Thus, the pushbutton can be turned between a locked position in which it cannot be displaced axially, and an actuatable position that is unlocked and in which the user can press on the pushbutton and displace it axially down and up, so as to dispense the fluid. However, the pushbutton always remains coupled directly to the valve rod, such that they are constrained to being axially displaced together, simultaneously.
In the prior art, dispensers are also known including a casing in which both the dispenser head and the reservoir are housed. The casing is provided with actuator means that make it possible to displace the dispenser head and the reservoir inside the casing in order to cause the pushbutton to project from the casing for actuation purposes. Once again, the pushbutton is directly connected or coupled to the valve rod, and they are thus displaced together, simultaneously.